urn:nasa:pds:uranus_occ_u102a_irtf_320cm:data:2200nm_radius_four_ingress_500m
1.0
Radial Profile of the Ingress Occultation of u102a (UCAC2 22794648) by Uranus Ring four
1.14.0.0
Product_Observational
French, Richard G.; McGhee-French, Colleen A.; Gordon, Mitchell K.
2020
uranus rings
uranus rings stellar occultation
uranus rings stellar occultation radial profile
Derived radial profile of the Uranus ring four from the occultation of star u102a (UCAC2 22794648). This profile is based on the plane of ring four.
2021-04-05
1.0
Initial version
1992-07-08T09:46:54.6805Z
1992-07-08T09:47:10.3829Z
Science
Derived
Derived radial profile of the Uranus ring four from the occultation of star u102a (UCAC2 22794648). This profile is based on the plane of ring four.
Infrared
Ring-Moon Systems
Ring Occultation Profile
Earth-based Observations of Uranus System Stellar Occultations
Observing Campaign
urn:nasa:pds:context:investigation:observing_campaign.earth-based-uranus-stellar-occultations
data_to_investigation
IRTF 320cm Telescope
Infra Red Telescope Facility-Maunakea
Host
urn:nasa:pds:context:facility:observatory.irtf-maunakea
is_facility
IRTF 3.2m
Telescope
urn:nasa:pds:context:telescope:irtf-maunakea.3m2
is_telescope
Generic InSb High Speed Photometer
Instrument
urn:nasa:pds:context:instrument:multi-host.generic_insp_hsp
is_instrument
Uranus Rings
Uranian Ring System
Ring
urn:nasa:pds:context:target:ring.uranus.rings
data_to_target
four Ring of Uranus
Ring
The four ring of Uranus.
Center of motion: Uranus;
LID of central body: urn:nasa:pds:context:target:planet.uranus;
NAIF ID of central body: 799.
urn:nasa:pds:context:target:ring.uranus.four_ring
data_to_target
SPK
ura111.bsp
SPK
vgr2.ura111.bsp
SPK
earthstns_itrf93_040916.bsp
BPC
earth_720101_031229.bpc
LSK
naif0012.tls
These kernel files were used in the generation of the products in the parent bundle. Some or all of them may not have been used directly in the generation of this product.
stellar
both
ingress
Y
poor
4
Y
four
UCAC2 22794648
1.75
0.5500
0.1500
0.020000000
double pole
0.12500
0.02500
1903.00000
2416.00000
0.50000
0.24455
0.26071
1992-07-08T00:00:00.0000Z
35214.6805
35230.3829
-236139126.1356
-236148354.6378
1992-07-08T07:12:50.4766Z
1992-07-08T07:13:06.1783Z
-236148370.3395
-236139110.4332
1992-07-08T09:46:54.6805Z
1992-07-08T09:47:10.3829Z
42385.0000
42785.0000
18.7169
18.8475
358.8861
359.0167
-60.47479
29.52521
0.02
3.0
urn:nasa:pds:uranus_occ_support:document:earth-based-uranus-stellar-occultations-user-guide
data_to_document
The Users Guide for all of the Earth-based Uranus system occultations.
urn:nasa:pds:uranus_occ_u102a_irtf_320cm:data:2200nm_counts-v-time_rings_ingress::1.0
data_to_calibrated_product
Normalized counts vs. time for the ingress ring occcultion.
urn:nasa:pds:uranus_occ_u102a_irtf_320cm:data:2200nm_ring_four_ingress_sqw
data_to_associate
Input data and results of non-linear least squares fits of a diffraction square well model to the occultation profile of u102a (UCAC2 22794648) by Uranus Ring four.
urn:nasa:pds:uranus_occ_u102a_irtf_320cm:browse:2200nm_obs_geom
data_to_browse
Diagram of the Uranus system showing the occultation track.
urn:nasa:pds:uranus_occ_u102a_irtf_320cm:browse:2200nm_earth
data_to_browse
Diagram of the view of the Earth from Uranus at mid-occultation Time.
urn:nasa:pds:uranus_occ_u102a_irtf_320cm:browse:2200nm_alt
data_to_browse
Plot of the altitude (in degrees) of Uranus and the sun relative to the horizon over the duration of the occulation.
urn:nasa:pds:uranus_occ_u102a_irtf_320cm:browse:2200nm_radius_equator_ingress_1000m::1.0
data_to_browse
Low resolution plot of optical depth vs. radius based on the equator plane of Uranus.
urn:nasa:pds:uranus_occ_support::1.0
data_to_resource
The support bundle for all of the Earth-based Uranus system occultations.
urn:nasa:pds:uranus_occ_support:data:uranus_occultation_ring_fit_rfrench_20201201::1.0
data_to_resource
The fitted model of the ring system upon which the data are based.
u102a_irtf_320cm_2200nm_radius_four_ingress_500m.tab
profile-data
2021-04-05T14:38:32Z
0
262
UTF-8 Text
Provides the column headers, separated by commas, for the data table.
262
801
This is a derived occultation profile of the Uranus ring four generated from an earth-based stellar occultation. The data are interpolated from the original time series onto a uniformly spaced grid in the ring plane radius, including the possible effects of inclination with respect to the equatorial plane. When conditions allow, the data have been normalized in units of stellar intensity, and include the observed event times as well as the ring intercept time when the stellar signal reached the ring plane.
Carriage-Return Line-Feed
14
0
205
Ring Radius
1
1
ASCII_Real
12
km
Radial distance of the occultation intercept point (middle of the bin) from the center of the planet, in km. Distances are measured along the plane of the specified ring.
Ring Longitude
2
15
ASCII_Real
8
deg
Inertial longitude on the ring plane corresponding to the midpoint of the bin.
Observed Ring Azimuth
3
25
ASCII_Real
9
deg
Angle measured at a point in the ring plane,
starting from the direction of a photon heading to the observer, and
ending at the direction of a local radial vector. This angle is
projected into the ring plane and measured in the prograde direction.
0
Normalized Signal
4
36
ASCII_Real
10
Normalized signal during this
radius bin, in units of the unocculted stellar signal, such that
1.0 corresponds to the full unocculted star signal and
0.0 corresponds to no counts from the star (a completely opaque ring).
Normalized Signal = (Mean Signal - Background Model)/(Unocculted Star Model)
This is an approximate normalization, based when possible on regional polynomial fits.
For high-precision photometry of ring events, use locally computed normalization.
999.999999
999.999999
Mean Signal
5
48
ASCII_Real
16
Mean counts received by the instrument during this radius bin. The background
signal has not been subtracted. Refer to Note Flag for guidance on validity of data.
999999999.999999
999999999.999999
Mean_Signal_Uncertainty
6
66
ASCII_Real
16
The uncertainty in the mean signal level expressed as the standard
deviation per radial bin, computed when possible from the adjacent
mean signal level over a span of (typically) N=50 free-space radial
samples on each side for which the Note Flag is 0 or 1,
or at least N total nearby samples for which the Note Flag is 0 or 1.
For cases with fewer than N total nearby samples available, and the
Note Flag is 0, or for all cases when the Note Flag indicates a ring
occultation event, the uncertainty is estimated by interpolation from
nearby free-space values. Otherwise, the value is set to -1.
999999999.999999
999999999.999999
Observed Event Time
7
84
ASCII_Real
16
second
The instant at which photons were received at the observer location. It is
represented in the Universal Coordinated Time system, as a number of elapsed
seconds since the time given by the reference_time_utc attribute specified in this file.
It refers to the middle of the bin.
Observed Event TDB
8
102
ASCII_Real
17
second
The instant at which photons
were received at the observer location. It is represented in the
'Barycentric Dynamical Time' system, as a number of elapsed
seconds since the J2000 epoch. It refers to the middle of the bin.
Ring Event Time
9
121
ASCII_Real
16
second
The time at which photons left the ring plane. This time is earlier than the
associated observed event time by an amount equal to the light travel time. It is given
as a number of elapsed seconds since the time given by the reference_time_utc attribute specified in this file.
It refers to the middle of the bin.
Ring Event TDB
10
139
ASCII_Real
17
second
The time at which photons left the
ring plane. This time is earlier than the associated Observed Event TDB
by an amount equal to the light travel time. It is represented in the
'Barycentric Dynamical Time' system, as a number of elapsed
seconds since the J2000 epoch.
Background Model
11
158
ASCII_Real
16
Model of the non-stellar background signal (which may vary over the course of the occultation)
due to instrumental offsets applied during the recording and/or sky brightness and contributions from
reflected sunlight from the rings and planet.
999999999.999999
999999999.999999
Unocculted Star Model
12
176
ASCII_Real
16
Model of the unocculted star
signal as a function of ring plane radius. This may be affected
by variations in atmospheric transparency and other time-dependent
effects. Note that sky level checks in the data, often just
after an individual ring occultation event, compare the background
sky level to the measured intensity not only of the occultation star
but also the contribution of the brightness of the planet and rings
in the photometric aperture, which can contribute several percent
of the unocculted stellar flux to the total counts observed
when the aperture is centered on the occultation star. When possible,
this effect has been included when computing the model of the unocculted star
signal listed here.
999999999.999999
999999999.999999
Number Of Samples Per Bin
13
194
ASCII_Integer
4
Number of raw time bins contributing to this radius bin.
When the radially interpolated signal subsamples the raw data, this
value will be 1.
Note Flag
14
200
ASCII_Integer
4
A numerical flag that associates
specific comments with individual data bins. When more than one
comment applies, the values are summed. The values and their
associated comments are:
0: radius and longitude are based on Uranus equatorial plane.
1: radius and longitude are based inclined ring plane model
referred to in metadata associated with file.
2: observed ring occultation event
4: telescope pointed to nearby sky for background level check
8: input signal from time source, not from photometer on telescope
16: line of sight intersects planet
32: dawn/dusk - rapid background level change;
no background or star intensity estimate.
64: unreliable data (e.g., clouds, telescope
guiding error, or instrument adjustment);
no background or star intensity estimate.